package demo07System;

public class Demo02 {
    public static void main(String[] args) {
        long l1 = System.currentTimeMillis();
        String str="";
        for (int i = 0; i < 100000; i++) {
            str+=str;
        }
        long l2 = System.currentTimeMillis();
        System.out.println("所需要的毫秒值："+(l2-l1));
    }
}
